01 -
Heat your oven to 350°F, and prep two half-sheet pans (18×13-inch) with parchment paper, sprayed lightly. Toss the cake mix, sugar, water, eggs, vanilla, and oil into a stand or handheld mixer and mix for about a minute. Add in flour, salt, and sour cream, then beat for 2-3 minutes until it’s totally smooth.
02 -
Pour the batter into the two pans, smoothing it out evenly; these layers will be thin. Bake for 15-18 minutes until done. Once out, let them cool for half an hour at room temperature, then chill in the fridge for another 30-60 minutes.
03 -
On medium-high, whip up the marshmallow fluff and butter until creamy, about a minute. Toss in powdered sugar, vanilla, salt, and a couple of tablespoons of cream, mixing until creamy again. Add a little extra cream if needed—it should spread easily but not be runny.
04 -
Use a 3-inch heart-shaped cookie cutter to make 32 cutouts. On half of these, spread some of the filling, then place the other half of the hearts on top. Place them on a sheet pan lined with parchment and put them in the freezer for an hour.
05 -
Pop the almond bark into a microwave-safe bowl. Heat it in 30-second bursts, stirring each time, until melted. Stir in the Crisco until smooth. Save about ½-1 cup of melted almond bark for decorating later. Add pink gel food coloring into the remaining almond bark. Let it sit for a couple of minutes to cool slightly.
06 -
Take the frozen hearts and dunk them into the pink almond bark, placing them onto a parchment-lined cooling rack to set. After 10 minutes, drizzle the reserved white almond bark over the hearts in swirls or patterns to fancy them up.